Treating hydrocarbon oils



Aug. 29, 1933. A. s. BAILEY Er AL TREATING HYDRocARBoN oILs Filed Feb. 12, 1929 f 1,924,534 n o v 'l o Y TREATING HQYDltooAltBoN oILs Addison S. Bailey,- Houston, Tex., and EdwardM'.`

' Reynolds; Tulsa; i0kla.,vassignors to The Texas Company, NeWYork, N. Y., a corporation oi?v Delaware 'o u A Application Februeryilaflezs. serial No. 339,306

` y y13 CieimsoV ((11.196-49) This invention relates'generally to the conver` inventionvand constitutngvan embodiment i sion of higher boiling hydrocarbons into lower thereof.

boiling ones and has particular reference. to Vcer-l Figure is; an enlarged section` taken on the tain improvements inthe treatment of liquid oil line 2 2 o f Figure 1. y Y i or residue developed in the cracking reaction. n the apparatus thusillustrated a .so-called 60 It has been sought to utilize theheat contained coil and drum or tube and tank type 0f Craekihg in residual or liquidoil as Withdrawn from a s ystemisshown but it is to be understood that .Y cracking chamber to effect the distillation therethe, invention may 'Well be practiced. in cfm'rlec-` of, for the purpose of recovering therefrom gasotiOh With Other types 0f Cracking `PlOeeSSe'S- The Y lo line or naphtha distillates aswell as heavier dis- `eraeking apparatus ihCludeS aY heating COil v10 65 tillates, by directing the oil Withdrawn from the and a cracking still Vl1 With a charging line 13 cracking chamber into anfexpanision chamber or and pump i4 adapted `for introducing a suitable still operating at reduced pressureoto, effect the ellargingvv stoel:` tOjthe heating` O Oil arid with a distillation. One iof the chief difficulties experi-` transfer line 151for conducting thelglleatedoil enced in such procedure is that when, the disfromY the coil 10 to the/ still 11.`; 'I he heating coil 70 charge of residue from the cracking stillintothe iS ShOWh diSpOSed iIl a furnace4 16 WhChiS ih-g tar distilling chamber is effected by taking shots tended t0 Supply Suiiieieht heat, *SOthat the; Oil in a customary manner the residue ldistilling may preferably; be bI'Ought tO-a'eraekirlggterh7- ,chamber is necessarily subjected Vto great iluctuaperature befOre it leaVeS the Oeil- The 'Still `11 tions in pressure which disturbs theconditions` may either be heated ,in a furnace' Ornsulated 75 of distillationtherein.` Itis desirable to main`` to prevent O1' retard IOSS4 Ofnlneatylf` vdesired a tain the residue distilling chamber at substanpluraltYOf Stills maybeemployedinlieuofithe t tially auniform pressure throughoutrth'e distilla- Single Still' Shown iA 'Vapor line 117 SeVeS t0 `tion in order that theproducts obtained in 'the Conductvapors from thestill'to a dephieemato distillation maybe constantlykept at the tests 0r flaetonatug COlumIl V13 Whiehgmay be yin the 30' desired. The operation in the residue distilling form ,0f a, bubble tower 01" a DaekedytOWer OrOf chamber may be smoothed out somewhat when any other Suitable design AYaPOI line 19 C011- a single residue' stripping unit is operated in conduets the Overhead VapOr fraCtiOrl tO a COhdehSer `junction with valolurality ofV batteries of pres- 20 and a I'eeiVihg drum21. pleierably haYinga n sure stills by timing the taking of shots from the ValVed gaS Outlet 22 Iand a ValVedliCOndensate 95 several batteries and the Vsame result can be ob Outlet 23 iS P1`0Vdedf01` Collectingthe distillate. tained,valthough to a more limited extent, when a Aline 24 iS ShOWrreXtehdihg t0 a hOt Oil pump 245 single battery composed of a plurality of stills having a discharge line 2 6 SO that reflux @Orldeh-` j is used by properly timing rthe shots takenffvrom Sete from the fraetiohatih'g' COlumIl- 18 I riayfbe o the several stills, but even these procedures do not forced into theQCOlQ10 Y 90 eccomplish that even distillation in the distilling Atal Or'residue draw-Off line 27 iS'ShOWn ex# Chamber which is desirable, l tending to a tar main 28 to which arealso con-v In accordance with my invention a surge drum rented a pluralityY 0f lines as' 27a, Nutte., `each Y or chamber is provided between the cracking OfWhiCll mayeXteud t0 azseparatesbattery or. 4o chamber and the residue distilling chamber end raekns unit uwtshgwnh- YThe.tf=u ,1 11 ain 4281s 95 jthe liquid oil is Withdrawn from the cracking equipped With a pressure, reducing Valve 29Vand chamber into the surge drum Where a certain eXteIidS'tO a Surge drum 30 A line 3l iS prO- amountr of Yexpansion is allowed to take place. Vided fol' Conducting, the Oil from the surge drum The surge drum operates to cushion the shock of Y304l t0 a distilling Chamber v342. AS eleerly Sho-Wn 1 the shots from the cracking chamberY end-thus in :Figure 2 a' Preferred Lmethod 0f Construton loo permitthe liquidto be dischargedin a regulated 15130.' dl'mngethefconnectohs 29 and 371,;Wtl1 the manner into a distilling chamber wherein ap- Chamber 30 talgenfiduy 0f' the` Chambei- `Wtl1 4proximately constant. conditions may be .thus Such C OnStIuCtOna more 01' leSS IOtaly m9151011 maintaine 'o i `may be imparted to the material in thesurge i YIn order to more fully 'discloseimy invention Y Chamber that may' tend "t0 Settle-Out COkeahd 105"v reference will now be lhad tov the accompanying iV carbon therein. A line33 is shown near the bot` drawing which l illustrates f a preferred emboditem 0f the ChamberSOtl-lat if desired drags may ment of theinventionwherein: 'j 2 be taken onthe chamber 30 at intervals for the o' Figure 1 is a diagrammatic sectional elevation purpo'seofrpreventingthe chamber'from becomof an apparatus constructed in accordance with- Ving choked up'yvith4 accumulated coke. The 110 --the cushioning operation.

The distilling chamber 32 may be of any suitable' construction but in the preferred construc-l tion shown the lineBl entersat the upper end of the chamber and thus operates to direct the kmar terial from the'surge drum` over-a spreader orhood beneath which are a plurality of baies 62 to spread or lin'the descending liquid in order to thereby facilitate its vaporization. A steam line 36 is shown in the lower portion-of the distilling chamber for the purpose of supplying live steam, either saturated or superheated, to the chamber, although it may be stated that in many cases no steam or other carrier gas or other heating means may be employed, the heat contained in the residuevbeing adequate to effect the `desired distillation. The vapor line shown in the drawing includes an elbow 37, positioned'under.-

Y neath the `spreader'or hoodr35, .connected to a liquid levelin thedistilling. chamber; If desired,

theuflow vofi-materialithrougli the line-31 from the surge drum to the distilling chamber may be controlled by an automatic valve (not shown) .operated by the vcomparatively slight iuctuations in Y' pressure which may occurin the distilling chamaltered accordingly.

ber. A line'43` is provided for withdrawing vthe stripped residue from the chamber 32.

Two dephlegmators or fractionating columns 44 and 45 are-shown in the drawing for the tar or residuestripping unit with the vapor line 38 extending from the still 32 to the tower 44 and with 'a vapor line 46 extending from the tower 444 tothe'tower 45. The towers 44 and 45k may be in the form ofr bubble towers or'packed towers for'V inthe form of any suitable dephlegmating or'fractionating apparatus. Steam lines 47 and 48 are shownrnear the bottoms of the two towers 44 and 45,*respectivelyffor the purpose of introducing live steam into the towers to aid the distillation therein. Two towers are indicated for the purpose of .obtaining-two cuts or". heavy condensate but if it is desired to obtain a greater number of cuts or only a single cut of heavy condensatev the fractionating equipment'v may be Valvedv draw-off lines V4jl-lvand 50 extend from the towers v44 andl 45, respectively, ,to a common condensate line 51V which extends to a pump-'52v f having a discharge line 53 extending-tol the heating coil 10 sok that either one or both of the -reux condensates"withdrawn from the ftowers 44A and 45 maybe purnpxi Vdirectly to the heatingfcoilrlO. It is preferable to cycle back these,

condensates in a heatedA condition as Withdrawn from the towers and it may be observed that both the reflux condensate obtained from the tar stripper which is admitted to' the coil 10 throughrthe f been explained. v

Normally the 'surge drum 30 may be subjecti line 53 and the reflux condensate from the fractionating column 18 which is admitted through vthe line Y26 are preferably introduced into the heating coil Y at points therein at which the oil charge in the coil is at substantially the temperature ofthe reflux condensates introduced. Branch lines 54 and 55 are'shown connected to the lines 1 l ythe towers 44 and 45 may be vconducted VVto .tankage A vapor line r56 `is provided'for conducting theV overhead vapor fraction fromthe tower 45 to a condenser coil 57. The outlet of the coil 5'7 terminates in a trap 58 for trapping `out water V If steam is not used in the towers l44 and 45 thistrap may be omitted. A

from the condensate.

receiver 59 is shown for collecting the final light distillate. d p

Y In practicing the invention 'with the apparaperatures and pressures may beemployed. vHowever, in a preferred'-v example of the invention `conversion temperatures of the order of 750 F.

to 980 F. maybe maintained inthe still 11 under pressures of theorder of 260 to 600 pounds.

The evolved vapors 'are fractionated inthe col-l umn 18 from which reflux condensate is withdrawn and conducted to the heating coil l0 while the overhead vapor fraction is condensedin the condenser 2i) and/collected as a gasoline or naphtha distillate in the receiver 21. Tar or residue is withdrawn through the line 27 tothe'tar header Y.28 and passed thence through the pressure regulatine `valve 29 to the surge drum y30 and thence into the distilling chamber 32 as has heretofore ed to considerable variations in pressure dependent upon thefreduency and extent of the drags 'orshots taken-from the still llas well as from vthe, other batteries to which the lines 27a., 271;,

etc. are connected, in cases where itis desiredy the distilling Chamber 32. It is preferable to operate the distilling chamber under a pressure ap- A,

proximating orapproaching atmospheric; Ifk desired, a slight superatmospheric pressure, such for example as 5 -to 10 pounds, may be employed in thedistilling` chamber '32 which pressure facilitates the .discharge of productsV fromthe chamber. Pumps maybe employed in withdrawing 'the stripped liquid from the distilling chamber 32 as well as for withdrawingthe reflux condensates from the towers 44 and '45 and the final distillate fromthe receiver 59. For most puri Y poses it is 'unnecessary to employ a vacuum in the residueV distilling operation although the useof a vacuum is not precluded in the practice of the invention.-A It-'will be thus seen that the preswithin-comparatively wide limits.v ,i As a typical i example of the invention, however, lit Amay be stated that a Psuitablecracking operation may be 'carried on at a pressure of about 4G() pounds i in the still 11, Withthe pressure inthe surge drum 30 fluctuating between about 275 to' 50 pounds and 1 in' a regulated'quantity into the distillingcham'- continuous manner and thus directed in to the surge drum 3Q.

In carrying outl the process it is preferable, although not necessary, to carry on the fractionation of the vapors obtained in the tar stripping.

operation to such an Yextent as to obtain a naphtha or gasoline distillate in the receiver 59 of substane tially thel same boiling point as that of the pressure distillate collected in the receiver 21. yIt is likewise advantageous to employ the two towers 44 and to thus make two cuts of gas oil,rthe heavier of which may well'be returned to the sarnecrack'- ing system from which it was derived while the lighter out may be otherwise disposed oi as by'being subjected tolcracking at higher temperatures andpressures than thatof thecracking system from which it was derived;

Although theinvention has been described speciiically as applied to the treatment of residues obtained from cracking stills wherein distillation takes place during the rcracking reaction the in-` vention may-also be applied to processes in which the oil is subjected 'to cracking without con-y comitant `separation andf removal of vapor from the cracking chamber, the converted oil or vsynthetic crude', as it has sometimes been termed, be-

ing Awithdrawn from a high pressure reaction.' f

chamber, such for example as one operated under from 600 to poundsfpressure, and then discharged into the surge drum and delivered thence ber.

Although the surge drum opera-tion herein set forth is most usefull in cases where the removal of pressure tar from the cracking'stiils is carried on intermittently bytaking periodic shots or drags' from the stills it may also beernployed toad- Vantage in cases where thewithdrawal of residuey is continuous.

Obviously many modifications and variations of` the invention, as hereinbefore set `forth, maybe made without departingfrorn the spirit and scope v thereof, `and therefore, `only such limitations should be imposed as are 'indicated 'in the appended claims. v i

Iclaim:4 y .v

1. In a process of distillation in a reduced pressure distilling zone ofthe hot-residue taken from a superatmospheric pressure conversion zone,'the process that comprises rst introducing the residue into a surge chamber interposed between the superatmospheric pressure conversion Zone and the reduced pressuredistilling zone, maintaining saidchamber at a rangeof pressures materially belowsaid conversion Zone pressure without-dis-I tilling oiT a ldistillate from 'said chambenldistilling the hot residue under the reduced pressure,

` not materially aiected by variations thatmay occur in the discharge'of material from said conversion'zone, in the distilling zone by means of its own contained heat, separating the oil charged into` said reduced .pressure distilling zone into if fractions comprising a fuel oil, a plurality of gas oils, and a naphtha, and' returning one of said gas oil fractions to thepressure conversion zone. 2. In a process forconvertinghigher boiling hydrocarbons into lower boiling ones by the application of heat' and pressure Vthe steps comprising" passing a developed residueintermittently into a'lower pressure Zone wherein pressurevariations may takeplace without the separaterel moval of vapor, passing' all-products ltherefrom in a" regulated continuous streamf into a flashA chamber maintained under a substantially "constant and still further reducedpressure andpassing ,aiv resulting overhead vapor to a dephlegmating Zone while withdrawing a relatively heavy residue.

3. In .the conversion of higher boiling hydrocarbons into 'lower vboiling Vones by the application of Yheat and".pressure,A theprocess that comprises intermittentlyjpassing a residue developed j `in the conversion into alower pressure zone sure, passing'a resulting overhead vapor toa` `dephlegrriating `zone, withdrawing va relatively" heavy liquid residue froml Vsaid flashlchamber,

passing the `lighter; Vaporous constituents from said 'dephlegrnating' zone to a' iurther ,dephleg--,

matingv zone while condensing arelatively heavy fraction said iirst` dephlegmating zone, and

ldelivering afinal `vapor 'fr'ornfsaid second 'de phlegmating zone toxa'lcondenserto form a desired ultimate distillate while condensing in saidV Zone a fraction lighter than the fraction c ondensed in the first dephlegmatingzone` but heavier than the ultimate distillate. i

4: In the treatment of hydrocarbon oils whereinthe oil is subjected to cracking in a reaction chamber under superatniospheric pressure `and `'wherein'productsare withdrawn fromthe reaciis tion' chamber and subjected lto 'distillation in a distillingapparatus maintained under a ylowerv pressure than; that of the reaction chambertou effecta separation of said'products into distillate andresidue, the 4process that'fcornprises delivering .the withdrawn'productsyprior to said distillation, into an expansion chamber from which'no separate vapor fraction is'withdrawn and which is v maintainedunder ,a range of pressures materially v below that of thevreacti'on V"chamber and passing a regulated quantity of said products thence tov the distilling apparatus kwhich is `operated so as notto be materially affected by lany variations I that'may occur inthe dischargefof material from l said reaction chamber; Y. v

5. In the treatment of hydrocarbon oils wherein the oil is subjected to cracking in a reaction chamber under superatmospheric pressure and wherein products ,are withdrawn from the reaction chamber and subjected to'auto-distillation in a'distilling apparatus maintained under a lower pressure than `that or thereaction chamber to eiiect'separatiori vof said products intodistillate andresidue, the process that comprises deliver- Y ing thefwithdrarwn' product'syprior to said distillation, Vintoan expansion chamber from which no separate vapor fraction isl withdrawn and which is maintained under a range of pressuresV lmaterially below .that ofthe reaction Vchamber and -`passing'a continuous stream of products,

with contained heat sufcient to eiect distilla-'" tion, thence to the distilling apparatus.

6. In the treatment of hydrocarbon oils Wherein the oil isjsubjected to cracking in a reaction chamber under. superatmospheric pressure and quantity of the oil is accumulated under a range of pressures V materially below that of the reaction chamber and under conditions suchthat the density of the products inthe accumulating chamber may vary,'depende'nt on ,the inux of material from the cracking chamber, delivering Aa regulated stream of material to the distilling apparatus and carrying out the distillation in a controlled manner not materially aiected by any 1. variations that may occur Vin the discharge of materiall from the cracking chamber.

'7, rIn the treatment of hydrocarbon oils whereinthe oil isisubjected to cracking and distillation under superatmospheric ypressure in a cracking still, the' process that comprises withdrawing residue rom'the cracking still and expanding it into a chamber maintained under a materially l lower pressure without distilling off'a distillate and 4passing `the' expanded oil into a distilling chamber maintained under a still lower pressure whereink distillation to effect a stripping of said residue takes place said distillation Vbeing not materially affected by any Variations that may occur in the discharge'of material from said cracking still. r y

V8. ln the treatment of hydrocarbon oils where-,-

in the oil is subjected to cracking and distillationv y jecting hydrocarbon oil 'to cracking in a reunder superatmospheric pressure in a cracking still, the process that comprises delivering residue, from the cracking still inshots to a' Surge,

chamber maintained at lower pressures than that of the cracking still, passing products substantially continuously from the surge chamber to a distilling chamber maintained at lower pressure than that or" the surge chamber and wherein distillation occurs without distilling off a distillate l from the surge chamber, permitting iiuctuation of pressure to take place therein'with consequent compression and expansion of contained products, dependenton the influx ofY materialfrom the cracking still, to thereby largely absorb the 'effect of the intermittent delivery of material to thesurgechamber and promote an'even distillation inthe distilling chamber;Y

9. The process ofrtreating hydrocarbon oilsk that comprises subjecting vhydrocarbon oil in a plurality or separate bodies to cracking under Y superatmospheric pressure, withdrawing oil from the several bodies of'oil undergoing cracking and delivering the 'withdrawn oil into a common accuniulatingiA drum in which iii-ictuationsofk pressure and consequent compression and expansionl of contained products, dependent on the influx of material vfrom the several bodies of oil, are permitted to take place without distilling off a distillate, and continuously passing oil; from the accumulating drum to a distilling apparatus in which the oil is ysubjected to' distillation at lower pressure than that ofv the accumulatingA drum.

l0.Y The method oftreating residue from a pressure cracking still which comprises intermittently deliveringv residue fromvthepressure still to a surge chamber maintained under a-lower pressure than that of vsaid pressure Ystill and wherein coke` Y is permitted' to settle out and the eiectof the` intermittent delivery of residue is absorbedr or cushioned without distilling ofi Va distillate, passing a substantially continuous stream of settled oil from the surge chamber to a distilling charnber where distillation takes place under a further reduced pressure and periodically withdrawing additional oil from the surge chamber from near the bottom to eifectremoval of'accumulated coke therefrom. Y Y

11. In the treatment of hydrocarbonoils Wherein the oil is subjected to cracking inV a reaction chamber under superatmospheric pressure and wherein products are withdrawn 'Y from the rein a distilling apparatus maintained under lower pressure than that 0I the reaction chamber, the

y process that comprises deliveringy the withdrawn products, prior to said distillation, into an expansion chamber from which no separat'e'vapor trace tion is withdrawn and which is maintained under a range of pressures materially below that of theY reaction'chamber and distilling apparatus, passing a regulated quantity of oil with contained heat sufficient to eiect distillation, from said eX-l pansion chamber to thelower pressure distilling apparatus which is so operated as not to be materially afiectedby any variations that may occur in the discharge of material `from Ysaid reaction chamber, subjecting resultant vapors to fractionation to form a condensate andrconducting said condensate to the reaction chamber.-

12. A process for the cracking and flash distillation of hydrocarbon oils that comprises subaction chamber under superatmospheric pressure, withdrawing products froml the yreaction chamber and passing them into a surge chamber from which no separatevapor fraction is withlow substantially constant pressure approaching 1 atmospheric.

13. A process V:for the 'cracking and flash distillation of hydrocarbon oils that comprises sub'- jecting hydrocarbon oil to .cracking in a reaction l9o actionchamber and subjected to rauto-distillation drawn, maintaining said surge Ychamber under ,v

chamber under superat'rnospheric pressure of the '130 order of 400 pounds, withdrawing products from the reaction chamber and passing them into a surgeV chamber from 'which no separate vapor fraction is withdrawn, maintaining said surge chamberv under a range of pressures materially 1 below that of the reaction chamber and permitting the pressures in the surge chamber to fluctuate within a range of the order of 275 pounds to 50 pounds, passing a regulated quantity ofV oil with contained heat suiiicient to eiect distilla- 1 0 tion from said surge chamber to angauto-distilling apparatus and subjecting the oilto distillation` therein under a low superatmosphervicA pressure of the order of 10 to-15 pounds, ADDISON 1s. BAILEY.

EDWARD M. REYNOLDS. 

